Heliox in respiratory failure from obstructive lung disease

To the Editor: There have been sporadic reports of the use of mixtures of helium and oxygen (heliox) as therapy in obstructive lung disease.¹–³ We describe a patient with respiratory failure for whom the use of heliox averted the need for intubation. A 64-year-old woman with obstructive lung disease and episodic bronchospasm was admitted to the hospital after five days of dyspnea and wheezing. The physical examination and chest film supported the diagnosis of an exacerbation of obstructive lung disease. The arterial-blood gas measurements on admission, with the patient breathing 4 liters of oxygen per minute, were as follows:.  . .